广西合浦海水珍珠变黄机理新议

海水珍珠缓慢变黄的传统解释是无机相文石不稳定向方解石转化这个不可逆过程造成的.然而作者通过肉眼观察、光学显微镜观察、H2O2漂白体系使变黄的海水珍珠重新变白实验及X射线粉晶衍射分析,均表明传统解释可能存在错误,变黄的海水珍珠无机相没有发生明显的相变,故推测珍珠内有机相的变化是珍珠变黄的主要原因.     

分光光度法测定海洋河弧菌510脂多糖

本文研究了直接测定海洋河弧菌 (vibrio fluvailis) 5 10脂多糖的分光光度法。利用 1,9-二甲基亚甲蓝 (DMB) ,在适当条件下同脂多糖发生染色反应 ,在 5 5 0 nm波长下 ,反应体系的吸光值同脂多糖含量呈线性相关。相关系数为 0 .9993,最低检出限为 10 μg/m L,相对标准偏差为 1.6 2 ,平均回收率为 (10 5± 2 .18) %。     

A combined numerical tidal model for the Hangzhou Bay and Qiantang River

-In order to avoid prescribing open boundary condition on the upstream side of the Hangzhou Bay, in numerical simulation of the tides and residual currents of the Bay, a 1-D model for the Qiantang River is connected to the 2-D model for the Hangzhou Bay. The harmonic constants of diurnal constituent [ (K1 O1)/2],semidiurnal constituent (M2) and shallow water constituent (M4) are obtained. The results produced by the combined model are in better agreement with the observed ones than those produced solely by the original 2-D model. The combined model gives much more reliable results for tide-induced residual water level and current.     

鲢鱼(Hypophthalmichthys molitrix)摄食强度和节律的实验研究

报道用室内实验方法对鲢鱼摄食强度和摄食节律的研究结果,探讨了影响它们的因子。提出鲢鱼在不同水温、不同花粉密度及不同鱼规格下的摄食量的统计分析。指出:食粒密度和水温与摄食量正相关,而鱼规格与摄食量负相关;食粒密度对摄食量影响最大(P<0.01),其次为水温;水温和食粒密度在影响摄食量的过程中可能有一定的交互作用。鲢鱼摄食强度在室内条件下也具明显的昼夜节律。在食粒规格较小、密度较低且溶氧充足条件下,鲢鱼夜晚非但不停食且出现摄食率次高峰。在本实验条件下,鲢鱼的日摄食节律与水温和光照无关,可能受饵料可得性和自身的生物钟节律等制约。     

On the long-term joint distribution of characteristic wave height and period and its application

By analysing the scatter diagrams of characteristic the wave height H and the period T on the basis of instrumental data from various ocean wave stations, we found that the conditional expectation and standard deviation of wave period for a given wave height can be better predicted by using the equations of normal linear regression rather than by those based on the log- normal law. The latter was implied in Ochi' s bivariate log-normal model(Ochi. 1978) for the long-term joint distribution of H and T. With the expectation and standard deviation predicted by the normal linear regression equations and applying proper types of distribution, we have obtained the conditional distribution of T for given H. Then combining this conditional P(T / H) with long-term marginal distribution of the wave height P(H) we establish a new parameterized model for the long-term joint distribution P(H,T). As an example of the application of the new model we give a method for estimating wave period associated with an extreme w     

THE VERTICAL MIGRATION OF DIATOM IN LITTORAL OF XIBIAN AND XIAO''AO

The vertical migration of diatoms in mud-flats was studied in littoral of Xibian, Longhai County and Xiao'ao, Lianjiang County, the dominant species being Gyrosigma spencerii and Hantzschia virgata respectively. Both light and tide are important factors affecting the vertical migration of diatoms. With the advent of tide, the diatom community disappears from the surface. It reappears gradually when exposed to light. In the dark, the diatoms never appear in great quantity on the surface in laboratory or in littoral. Whether in the light or in the dark, the diatoms aggregate in maximum numbers in the upper 2 mm of the sediment. But when the tide has covered the sediments for 4 hr, Hantz. virgata penetrates the mud down to a depth of 14 mm, Gy. spencerii, 12 mm. We have found that Gy. spencerii posseses phototaxis, but no tide rhythm and no day-night rhythm in our laboratory.     

卫星海洋遥感的发展和预报中心遥感应用

本文简要介绍了卫星海洋遥感的发展情况和可获得的海洋气象观测数据,介绍了预报中心卫星遥感的发展历史和现今状况,以及为海洋环境监测和预报提供的海洋遥感信息产品,并给出了部分产品示例.     

凡纳滨对虾生物学及养殖生态学研究进展

凡纳滨对虾原产于太平洋沿岸水域秘鲁北部至墨西哥桑诺拉一带。1988年由张伟权教授引进我国。本文对国内外凡纳滨对虾生物学及养殖生态学的研究进行了总结，提出了凡纳滨对虾养殖生态学今后研究的方向。     

潮汐分析和预报的准调和分潮方法 Ⅱ.短期观测的分析

目前,调和方法仍然是潮汐的分析和预报中的一种主要的基本方法,其关键在于求得尽可能准确的调和常数。在湖汐分析中,经常遇到的是对于中、长期(半个月以上)记录的处理,对于这样的资料,已有许多良好的分析方法可以采用。但是,有时我们也会遇到需要处理的短期观测资料,特别对于潮流,由于对它进行观测比水位观测要困难,常常不能获得较长期的记录,而需要从短期记录中分析出调和常数来。处理短期记录的方法也有不少,其中较为常用的是英国海军部的几种方法。这些方法只能处理一次或二次周日观测记录,当观测天数较多时,只能分组进行计算得到几组调和常数,然后再求平均值由于各组的天文条件的差別,调和常数的准确度常常有相当大的差异,而计算平均值时却没有加权,这就影响了结果的可靠性。本文建议的方法将可以直接分析任意多次周日观测记录,因而简化了计算并能得到更准确的结果。     

固定化鲅鱼乙酰胆碱酯酶的制备及部分性质测定

酶的固定化是酶传感器制备过程中重要的1个环节.研究采用直接共价法固定鲅鱼乙酰胆碱酯酶（AChE）.制备方法为：0.1g CNBr活化的Sepharose 4B凝胶用1mmol/L的HCl充分溶胀后,与活力为10U的AChE溶液混合,于4℃下150r/min振荡8h.所制备的固定化酶活力回收率较高（96%）,对pH值和温度变化的适应能力均优于非固定化酶;在3个月保存期内,前者的活力损失13%,而后者的活力则下降89%.这说明固定过程能够大大提高AChE的抗逆性和保持酶活力的稳定,有利于酶传感器的制备.